II. STARGRASP Software Overview

See also Command syntax notes

These are the five layers of interfaces to the STARGRASP controller system. Each is built on only the next lower layer:

A. Demo Scripts

Our example/template script commands run on the STARGRASP pixel server. They are implemented in Bourne Shell and are primarily for demonstration -- a suggested way to integrate a camera or set of detectors controlled by STARGRASP into a larger system. The scripts use toolkit level commands, described below, to control a group of controller boardsets.

B. Toolkit Level

The STARGRASP toolkit consists of C programs which a user or script can invoke on the pixel server host. Toolkit programs can be invoked on any host with the ability to connect to the controller using IP over Ethernet. The most important tools in the toolkit are those which receive log messages, boot the controller, send arbitrary commands, and retrieve FITS images. Additional engineering tools exist to visualize and optimize noise performance and generate clocking patterns.

C. STARGRASP C Libraries

Each of the toolkit tools are built on five main C Libraries. Users wishing to replace the Demo Scripts, or make their own customized tools that work in a similar fashion to the toolkit level can build their own programs by using the APIs at this level and linking with these libraries. Some of the APIs at this level are still evolving, so we recommend using the Toolkit tools instead, if possible.

D. Controller Socket Commands

The STARGRASP C libraries must accomplish all controller communication through a TCP socket on the controller's port 915 (by default.) The majority of these commands are sent by using grasp_cmd() (the C function, or the toolkit tool.) grasp_cmd is a pass-through to the extensive list of commands that the controller supports at the socket level. For diagnostics, many of these commands can also be typed manually if a serial console is connected to the controller, and most can be sent interactively with a tool such as "telnet" or "nc". A command exists to control each analog and digital function of the controller.

E. Registers and Clocking Instructions

Registers and Clocking Instructions are the lowest level API, used only by someone adding a new controller socket level command. All controller socket level commands are implemented in C code (downloaded as the stage2.srec to the controller) which modifies registers or address space, and/or writes instructions to the clocking engine.